This invention relates generally to identifying client computer systems, and more particularly, to methods and systems for identifying a client computer system based on a distribution of temporal differences between user input events.
Websites offer on-line services to their visitors which typically differ by provider. For example, governmental entities may provide information to their visitors while companies advertise products and hopefully conduct sales with their customers. It is known that providers spend a great deal of time and money developing their websites and expect a reasonable return on their investment. Successful websites are typically tailored to suit the needs of their visitors. Consequently, most providers monitor visitors to their websites and visitor usage. Information obtained through monitoring is used to tailor the services offered to each visitor.
Generally, visitors are identified via their client computer systems using a combination of hypertext transfer protocol (HTTP) cookies and device fingerprinting technology. HTTP cookies are typically used to identify visitors across multiple browsing sessions. However, HTTP cookies can be deleted between sessions, so it is possible that identification with cookies cannot be achieved. When cookies are not available, visitors may be identified using device fingerprinting. Device fingerprinting typically involves querying basic web browser configuration information from a client computer system or from client-side scripting languages such as Javascript or HTML canvas to collect partially unique information. Such partially unique information typically includes the browser version and/or configuration, information about the operating system, the central processing unit (CPU), screen resolution, languages configured in the browser, and rendering capabilities of the client computer system. Website providers store this information for each visitor. This information is partially unique because different client computer systems might have similar information. For example, the client computer systems of two different visitors might run the same operating system and have browsers configured in the same languages.
Many websites automatically conduct device fingerprinting when a client computer system visits the site. The obtained information is matched against stored visitor information from previous sessions in an effort to identify a returning visitor/client computer system. The information stored for the visitors may be used in many ways. For example, if the visitor is identified as a previous visitor, advertising tailored to the visitor's prior site usage may be displayed for the visitor to see in an effort to increase sales. However, a reliable match might not always be determined. As a result, the information collected using contemporary device fingerprinting technology may not accurately identify visitors resulting in lost opportunities for sales.